Auto ajax function

script.js

$ = jQuery;
var ws_ajax_manager = function(){
    // settings
    this.config = {
        content_selector: '.fl-page-content',
		loader_src: 'https://loading.io/spinners/double-ring/lg.double-ring-spinner.gif',

    };


	// Set the constructor function run on create class
	this.const = function(){
        $("body ").on( "click", "a[target!='_blank']", $.proxy( this.ajax_handler, this ) );
	};


	// function will run on every page change
	this.ajax_handler = function( e ){
		e.preventDefault();


		var $linkElm = $(e.currentTarget);


		var targetUrl = $linkElm.prop("href");
		if( targetUrl.indexOf( location.origin ) !== 0 ){
			return true;
		}

        e.preventDefault();


		$("body").append(
            '<style>' +
            '#ws_loader{' +
            '	width: 100vw;' +
            '	height: 100vh;' +
            '	position: fixed;' +
            '	background: #00000080;' +
            '	text-align: center;' +
			'	top: 0; left: 0; right: 0; bottom: 0;margin:auto;' +
            '}' +
            '' +
            '#ws_loader img{' +
            '	margin: 40vh auto 0;' +
            '}' +
            '</style>'
        ).append( "<div id='ws_loader'><img src='" + this.config.loader_src + "' alt='loading...' /></div>" );

        var content_selector = this.config.content_selector;

        var jqxhr = $.ajax({
				method: "GET",
				url: targetUrl,
            	async:false,
			})
			.done(function( response ) {
                history.pushState({urlPath:targetUrl},"",targetUrl);
                var $content = $( content_selector );

                var newHtml;
                newHtml = $(response).find( content_selector ).html();
                if( typeof newHtml == 'undefined' ) {
                    newHtml = $(response).filter(content_selector).html();
                }

                console.log( newHtml, content_selector );

                $content.html( newHtml );
			})
			.fail(function() {
				location.href = targetUrl;
			})
			.always(function() {
				$("#ws_loader").fadeOut( 1000, function(){
					$(this).remove();
				});
			});
	};

    // run the constructor
    this.const();
};

ws_ajax_manager();